package cn.xyy.common.utils;

import org.apache.commons.codec.binary.Base64;

import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;

public class SecretAESUtils {

	/***
	 * 加密
	 * 
	 * 
	 */
	public static String encrypt(String key, String text) {
		return encrypt(text, key, key);
	}

	/***
	 * 解密
	 */
	public static String decrypt(String key, String text) {
		return decrypt(text, key, key);
	}

	/**
	 * 加密方法
	 * 
	 * @param data 要加密的数据
	 * @param key  加密key
	 * @param iv   加密iv
	 * @return 加密的结果
	 * 
	 */
	private static String encrypt(String data, String key, String iv) {
		try {
			// "算法/模式/补码方式"NoPadding PkcsPadding
			Cipher cipher = Cipher.getInstance("AES/CBC/NoPadding");
			int blockSize = cipher.getBlockSize();

			byte[] dataBytes = data.getBytes();
			int plaintextLength = dataBytes.length;
			if (plaintextLength % blockSize != 0) {
				plaintextLength = plaintextLength + (blockSize - (plaintextLength % blockSize));
			}

			byte[] plaintext = new byte[plaintextLength];
			System.arraycopy(dataBytes, 0, plaintext, 0, dataBytes.length);

			SecretKeySpec keyspec = new SecretKeySpec(key.getBytes(), "AES");
			IvParameterSpec ivspec = new IvParameterSpec(iv.getBytes());

			cipher.init(Cipher.ENCRYPT_MODE, keyspec, ivspec);
			byte[] encrypted = cipher.doFinal(plaintext);

			return new Base64().encodeToString(encrypted);

		} catch (Exception e) {
			e.printStackTrace();
			return null;
		}
	}

	/**
	 * 解密方法
	 * 
	 * @param data 要解密的数据
	 * @param key  解密key
	 * @param iv   解密iv
	 * @return 解密的结果
	 */
	private static String decrypt(String data, String key, String iv) {
		try {
			byte[] encrypted1 = new Base64().decode(data);

			Cipher cipher = Cipher.getInstance("AES/CBC/NoPadding");
			SecretKeySpec keySpec = new SecretKeySpec(key.getBytes(), "AES");
			IvParameterSpec ivSpec = new IvParameterSpec(iv.getBytes());
			cipher.init(Cipher.DECRYPT_MODE, keySpec, ivSpec);
			byte[] original = cipher.doFinal(encrypted1);
			return new String(original).trim();
		} catch (Exception e) {
			e.printStackTrace();
			return null;
		}
	}

	public static void main(String[] args) {
		String key = "1234567linkadmin";
		String msg = "123456"; // 一个需要加解密的字符串
		System.out.println("【加密前】：" + msg);

		// 加密
		String secretArr = encrypt(key, msg);
		System.out.println("【加密后】：" + secretArr);

		// 解密
		String myMsgArr = decrypt(key, secretArr);
		System.out.println("【解密后】：" + myMsgArr);
	}
}
